Customize Windows 7 Theme Background Slide Show

1. Download Win7 themes here.
2. Go to "Control Panel" then "Folder Option", "View" Tab and select "Show hidden Files".
3. Once you have finished downloading, locate "C:/users/youraccountname/Appdata/Local/Microsoft/Windows/Themes/" 
4. Double click the folder of the current theme your using, then select "DesktopBackground" and then drag any background picture to this folder.

              To check, right click anywhere on desktop and select "Personalize" then click
             "Desktop Background". You should see all the background images you have used.


               Here is the screenshot of my customized Win7 theme background.